Configurable behavior for non-supported upgrade

[uprendis]

In a case if network activates an upgrade above current's node version:

• Show a warning if current node's version is below a network's version. If node was upgraded after the network upgrade, show a warning indicating a dirty node's state. (enabled by default)
• Shut down the node. (disabled by default)

[codecov-io]

Codecov Report

Merging #543 into develop2 will decrease coverage by 0.10%. The diff coverage is 20.00%.

@@             Coverage Diff              @@
##           develop2     #543      +/-   ##
============================================
- Coverage     43.74%   43.63%   -0.11%     
============================================
  Files           161      162       +1     
  Lines          9940     9978      +38     
============================================
+ Hits           4348     4354       +6     
- Misses         5178     5209      +31     
- Partials        414      415       +1     

Impacted Files	Coverage Δ
gossip/sfc_index.go	46.06% <0.00%> (-1.06%)	:arrow_down:
gossip/store.go	63.09% <ø> (ø)
gossip/store_network_version.go	0.00% <0.00%> (ø)
version/version.go	50.00% <33.33%> (-21.43%)	:arrow_down:
gossip/service.go	47.55% <42.85%> (-1.00%)	:arrow_down:
gossip/config.go	100.00% <100.00%> (ø)
evmcore/tx_pool.go	74.73% <0.00%> (-0.91%)	:arrow_down:
inter/ascii_scheme.go	81.90% <0.00%> (+1.90%)	:arrow_up:

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